Jaundice causes your skin and the whites of your eyes to turn yellow. Too much bilirubin causes jaundice. Bilirubin is a yellow chemical in hemoglobin, the substance that carries oxygen in your red blood cells. As red blood cells break down, your body builds new cells to replace them. The old ones are processed by the liver. If the liver cannot handle the blood cells as they break down, bilirubin builds up in the body and your skin may look yellow.